LITTLETON, Colo.—After expensive delays, NASA’s next mission to Mars is on track to embark next year. As spacecraft names go, this one is a mouthful: Interior Exploration using Seismic Investigations, Geodesy and Heat Transport. At NASA, and here at Lockheed Martin Space Systems Company, which built the craft, it’s just called InSight.

Designed to probe the planet’s deep interior and to eavesdrop on rumbling “Marsquakes,” the InSight lander will effectively take the planet’s temperature and measure its pulse. Now in final preparations on its path to the launchpad, the spacecraft is undergoing extensive thermal and vacuum testing and attended by a swarm of bunny suit–clad technicians. (The suits should help prevent microbial hitchhikers from catching a free ride to Mars when InSight lifts off.)

That launch could come as soon as May 5, 2018, according to Scott Daniels, manager of the assembly, test and launch operations phase for InSight at Lockheed Martin. The spacecraft is on target for transport in late February next year to California’s Vandenberg Air Force Base, where it will be mated with a rocket and prepared for launch. “Because we have an interplanetary launch window, it’s vital that we stay on schedule,” Daniels says. “The more [InSight] gets handled, the more likely something might go wrong. So one of my primary jobs is to make sure we get InSight off the planet as soon as possible and onto its November 26 landing on Mars.”